Keysight VXI Bus 75000 C Series User And Programming Manual page 48

Using the Keysight E1458A Digital I/O Module
PULSe
The PULSe handshake makes use of both the CTL and FLG lines. The input and
output operations are described below.
INPUT
1. The digital I/O module senses the
FLG line and waits for READY.
2. The digital I/O module sets the I/O
line HIGH.
3. The digital I/O module sets CTL
TRUE.
4. The peripheral senses the CTL line
and sets the FLG line to BUSY.
5. The peripheral places the data on
the data lines and indicates valid
data by setting the FLG line to
READY.
6. The digital I/O module senses the
FLG READY, returns CTL to FALSE,
and latches the input data.
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OUTPUT
1. The digital I/O module checks the
state of the FLG line (must be READY).
2. The digital I/O module sets the I/O
line LOW.
3. The digital I/O module places the
data on the data lines.
4. After waiting the programmed delay
time, Td, the digital I/O module sets
CTL to TRUE.
5. The digital I/O module then waits
another delay time, Td, and sets the
CTL line to FALSE.
6. The peripheral senses the CTL line
change, sets the FLG line to BUSY and
latches the data.
7. When the data is entered, the
peripheral returns the FLG line to
READY.
Keysight E1458A 96-Channel Digital I/O Module User Guide
Using the Handshake Modes